Adjustable spine distraction implant

ABSTRACT

An adjustable spine distraction implant alleviates pain associated with spinal stenosis and facet arthropathy by expanding the volume and/or cross sectional area in the spinal canal and/or neural foramen. The adjustable implant provides a spinal extension inhibitor. The implant includes elliptical or oval shaped adjustable member or spacer for positioning between and adjustably spacing apart the spinous processes.

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority of U.S. Provisional Patent Application Ser. No. 60/911,003,filed 10 Apr. 2007, is hereby claimed.

U.S. Provisional Patent Application Ser. No. 60/911,003, filed 10 Apr.2007, is incorporated herein by reference.

BACKGROUND

The spine includes a row of 26 bones in the back and allows a person tostand up straight and bend over. The spine also protects a person'sspinal cord from being injured. In people with spinal stenosis, thespine is narrowed in one or more of three parts: (1) the space at thecenter of the spine; (2) the canals where nerves branch out from thespine; and (3) the space between vertebrae (the bones of the spine).This narrowing puts pressure on the spinal cord and nerves and can causepain.

Caused by aging spinal stenosis is most common in men and women over 50years old. Younger people who were born with a narrow spinal canal orwho hurt their spines may also get spinal stenosis. Changes that occurin the spine as people get older are the most common cause of spinalstenosis such as: (a) the bands of tissue that support the spine may getthick and hard; (b) bones and joints may get bigger; and (c) surfaces ofthe bones may bulge out, which are called bone spurs.

In some cases arthritis, a degenerative condition, can cause spinalstenosis. Two forms of arthritis that may affect the spine are: (a)osteoarthritis and (b) rheumatoid arthritis.

Osteoarthritis is the most common form of arthritis and most oftenoccurs in middle-aged and older people. It may involve many joints inthe body where it wears away the tough tissue (cartilage) that keeps thejoints in place and can cause bone spurs and problems with joints.

Rheumatoid Arthritis affects most people at a younger age thanosteoarthritis. It causes the soft tissues of the joints to swell andcan affect internal organs and systems. However, it is not a commoncause of spinal stenosis but can cause severe damage, especially tojoints.

Some people are born with conditions that cause spinal stenosis. Forinstance, some people are born with a small spinal canal. Others areborn with a curved spine (scoliosis). Other causes of spinal stenosisare: tumors of the spine; injuries; Paget's disease (a disease thataffects the bones); too much fluoride in the body; and calcium depositson the ligaments that run along the spine.

In many cases there may be no symptoms of spinal stenosis, or symptomsmay appear slowly and get worse over time. Signs of spinal stenosisinclude: pain in the neck or back; numbness, weakness, cramping, or painin the arms or legs; pain going down the leg; and foot problems.

One type of spinal stenosis, cauda equine syndrome, is very serious.This type occurs when there is pressure on nerves in the lower back.Symptoms may include: loss of control of the bowel or bladder; problemshaving sex; and pain, weakness, or loss of feeling in one or both legs.

Because spinal stenosis has many causes and symptoms, treatment may berequired from doctors who specialize in certain aspects of thecondition. Health care providers can include: rheumatologists (doctorswho treat arthritis and related disorders); neurologists andneurosurgeons (doctors who treat diseases of the nervous system);orthopedic surgeons (doctors who treat problems with the bones, joints,and ligaments); and physical therapists.

As people age the amount of adverse spinal conditions tend to increase.For example, increases in spinal stenosis, such as central canal andlateral stenosis, along with the thickening of the bones making up thespinal column and facet arthropathy are expected. Spinal stenosistypically includes a reduction in the available space for the passage ofblood vessels and nerves which can impinge on these. Pain associatedwith such stenosis can be relieved by surgery. However, it is desirableto reduce the circumstances for which major surgeries are required toaddress stenosis.

Accordingly, it is desired to develop procedures and implants forsurgically addressing stenosis through minimally invasive procedures,and preferably such surgical procedures can be performed on anoutpatient basis.

U.S. Pat. No. 7,101,375 is incorporated herein by reference.

SUMMARY

One embodiment provides a minimally invasive adjustable implant andmethod for alleviating discomfort associated with the spinal column.

One embodiment provides a method and apparatus for relieving pain byrelieving the pressure and restrictions on the blood vessels and nervesassociated with the spine. This can be accomplished using an adjustableimplant and method which distracts the spinous process of adjacentvertebra in order to alleviate the problems caused by spinal stenosis,facet arthropathy, and similar conditions.

One embodiment provides an adjustable implant for relieving paincomprising an adjustable device positioned between a first spinousprocess and a second spinous process. The adjustable device includes avertebra expander or distractor.

One embodiment provides an adjustable implant which is positionedbetween a first spinous process and a second spinous process, andincludes at least one expandable distraction wedge or plate that canadjustably distract the first and second spinous processes as theimplant is positioned between the spinous processes as the wedging isexpanded and/or retracted. In one embodiment two expandable wedgingmembers are provided which can expand in substantially oppositedirections.

One embodiment provides an adjustable implant adapted for increasing thevolume and/or cross sectional area of the spinal canal and/or the neuralforamen as the implant is positioned between adjacent spinous processes.

One embodiment provides a method for relieving pain due to conditionssuch as spinal stenosis and facet arthropathy. The method includes thesteps of accessing adjacent first and second spinal processes of thespinal column and using an adjustable implant to distract theseprocesses a sufficient amount in order to increase the volume and/orcross sectional area of the spinal canal and relieve pain.

One embodiment provides a method and apparatus which includes implantingan adjustable device which can be adjusted in order to achieve a desiredamount of distraction and also maintain such distraction.

One embodiment provides an adjustable implant including a first portionand a second portion. The portions can be expanded and/or retracted inorder to achieve the desired amount of distraction.

One embodiment provides an adjustable implant which includes anadjustable body. The adjustable central body can include first andsecond portions which can be expanded and/or retracted in order toachieve the desired amount of distraction.

One embodiment provides an adjustable implant which includes a firstunit having an adjustable central body with a first wing at the firstend of the unit. The adjustable implant can includes a guide extendingfrom a second end of the unit and spaced apart from the first wing. Theadjustable implant can further include a second wing which can bedetachably connectable to the first unit, wherein the adjustable centralbody is located between the first and second wings.

One embodiment provides an adjustable implant with adjustable bodyhaving first and second wings, wherein at least one of the first andsecond wings is also adjustable relative to the other wing toaccommodate spinous processes of different sizes.

One embodiment includes an implant with an adjustable body to be able toaccommodate the anatomical structure of multiple spinous processes anddifferent sizes of spinous processes.

One embodiment includes an adjustable implant with an adjustable body,the adjustable body having an elliptical cross section. In otherembodiments the cross section can be circular, polygonal, square,rectangular, trapezoidal, quadralateral, etc. In other embodiments thecross section can be symmetric. In other embodiments the cross sectioncan non-symmetric, such as one shape of one side of the cross sectionand another shape on the other side of the cross section. For example,the cross section can have a half elliptical cross section on one sideand a rectangular cross section on the other side. In other embodimentsvarious permutations of the above specified shapes can be on each sideof the cross section.

Various embodiments of the method and apparatus can be used to increasethe volume and/or cross sectional area of the spinal canal therebyalleviating restrictions on vessels and nerves associated therewith, andreducing pain caused by such restrictions.

While certain novel features of this invention shown and described beloware pointed out in the annexed claims, the invention is not intended tobe limited to the details specified, since a person of ordinary skill inthe relevant art will understand that various omissions, modifications,substitutions and/or changes in the forms and details of the deviceillustrated and in its operation may be made without departing in anyway from the spirit of the present invention. No feature of theinvention is critical or essential unless it is expressly stated asbeing “critical” or “essential.”

FIGURES

FIG. 1 is an elevation view of the preferred embodiment of the apparatusof the present invention;

FIG. 2 is a top view of the preferred embodiment of the apparatus of thepresent invention showing the body portion of an adjustable implant,taken along lines 2-2 of FIG. 1;

FIG. 3 is an end view of the body portion, taken along lines 3-3 of FIG.1;

FIG. 4 is an end view of the body portion, taken along lines 4-4 of FIG.1;

FIG. 5 is a sectional view of the body portion taken along the lines 5-5of FIG. 1;

FIG. 6 is a sectional view of the body portion taken along the lines 6-6of FIG. 1;

FIG. 7 is a partial sectional view of the body portion in an expandedposition;

FIG. 8 is a perspective exploded view of the preferred embodiment of theapparatus of the present invention;

FIG. 9 is a fragmentary sectional view of the preferred embodiment ofthe apparatus of the present invention showing the threaded cap;

FIG. 10 is a sectional view of the adjusting screw;

FIG. 11 is a partial perspective view of the preferred embodiment of theapparatus of the present invention;

FIG. 12 is a fragmentary view showing second fixture or wing;

FIG. 13 is a fragmentary view of second fixture or wing;

FIG. 14 is a partial perspective view of the preferred embodiment of theapparatus of the present invention;

FIG. 15 is a partial perspective view of the preferred embodiment of theapparatus of the present invention showing adjusting of the control;

FIG. 16 is a perspective, partially exploded view of the preferredembodiment of the apparatus of the present invention illustratingimplantation;

FIG. 17 is a perspective view of the preferred embodiment of theapparatus of the present invention illustrating implantation;

FIG. 18 is a perspective view of the preferred embodiment of theapparatus of the present invention illustrating implantation;

FIG. 19 is an elevation view of an adjusting tool;

FIG. 20 is a fragmentary view of the adjusting tool taken along lines20-20 of FIG. 19;

FIG. 21 is a fragmentary view of the adjusting tool taken along lines21-21 of FIG. 19;

FIG. 22 is a side view of the body;

FIG. 23 is a side view of the body with adjusting tool engaged;

FIG. 24 is an end view of a second embodiment of the apparatus of thepresent invention;

FIG. 25 is a side taken along lines 25-25 of FIG. 24;

FIG. 26 is a side view of a fixture or wing part of the secondembodiment of the apparatus of the present invention;

FIG. 27 is a side view taken along lines 27-27 of FIG. 26;

FIG. 28 is a side view of a third embodiment of the apparatus of thepresent invention;

FIG. 29 is a view taken along lines 29-29 of FIG. 28;

FIG. 30 is a view taken along lines 30-30 of FIG. 29;

FIG. 31 is a perspective view of a fourth embodiment of the apparatus ofthe present invention; and

FIG. 32 is a perspective view of a fourth embodiment of the apparatus ofthe present invention.

FIG. 33 is a top view of an alternative embodiment of a second wingwhich is laterally adjustable relative to the first wing.

FIG. 34 is a side view of the wing of FIG. 33.

FIG. 35 is a side view of the wing of FIG. 33 taken from the lines35-35.

FIG. 36 is a perspective view showing wing adjustment tool beingconnected to the second wing of FIG. 33.

FIG. 37 is a side view showing the three pieces of wing adjustment tool.

FIG. 38 is a bottom view of the wing adjustment tool taken from thelines 38-38 of FIG. 37.

FIG. 39 is a bottom view of the wing adjustment tool taken from thelines 39-39 of FIG. 37.

FIG. 40 is a top view of the wing adjustment tool of FIG. 37.

FIG. 41 is a partial sectional view of the wing adjustment tool of FIG.37.

FIG. 42 is a top view of the wing adjustment tool of FIG. 37 connectedto the second wing of FIG. 33.

FIG. 43 shows the second wing being laterally adjusted.

DETAILED DESCRIPTION

FIGS. 16 through 18 are perspective views of a portion of a spinalcolumn 30. Spinal column 30 includes a plurality of vertebrae 40 withspinous processes (e.g., 100 and 110). Spinal column 30 also includesthe spinal cord and nerve roots (not shown for clarity). In oneembodiment the apparatus can be implanted to increase the volume and/orcross sectional area of spinal canal thereby alleviating restrictions onvessels and nerves 60 associated therewith, and reducing pain caused bysuch restrictions.

For purposes of implantation between adjacent first and second spinousprocesses 100 and 110 of spinal column 30 (see FIGS. 16 through 18),adjustable implant 200 can be configured as shown in FIGS. 1 through 43.First and second spinous processes 100 and 110 are exposed usingappropriate surgical techniques and thereafter, adjustable implant 200is positioned so that upper wedging member 700 engages first spinousprocess 100, and lower wedging member 900 engages second spinous process110 (e.g., see FIGS. 15,18). At this point, wedging members 700, 900 canbe caused to expand respectively in the directions of arrows 702 and 902(e.g., see FIG. 18) by manipulation of control screw 1500 with tool4030. Such expansion spreads apart or distracts spinous processes 100and 110 with the beneficial effect of enlarging the volume and/or crosssectional area of the spinal canal in order to alleviate restrictions onblood vessels and nerves.

Generally, adjustable implant can comprise body 210 along with first andsecond wedging members 700 and 900 (see, e.g., FIG. 1). First and secondwedging members can be mechanically expanded in the respectivedirections (and retracted in the opposite directions) of arrows 702 and902. As will be described below first and second wedging members 700 and900 can be operatively connected to adjusting screw or worm gear 1200.In one embodiment, when adjusting screw 1200 is turned in a firstdirection (e.g., in the direction of arrow 214 in FIG. 4, and in thedirection of arrow 1556 in FIG. 7) wedging members 700 and 900 expand ormove respectively in the directions of arrows 702 and 902. Whenadjusting screw 1200 is turned in the opposite direction (i.e., in theopposite direction of arrow 214 in FIG. 4 and arrow 1556 in FIG. 7)wedging members 700 and 900 retract or move respectively in the oppositedirections of arrows 702 and 902. For both expansion and retraction, acontrolled change in the state of expansion or retraction can beobtained through the use of a worm gear on adjusting screw 1200.

In FIGS. 7 and 15, an expanded position of wedging members 700 and 900is shown. In FIGS. 1, 2, 6, 11, and 14 a retracted or collapsed positionof wedging members 700, 900 can be seen. The amount of expansion (orcontraction) of wedging members 700 and 900 can be controlled byadjusting screw 1200 and control screw 1500.

In one embodiment a control screw 1500 can be operatively connected toadjusting member 1200 such as by a worm gear connection. Control screw1500 can be placed in bore 300 of body 210 (e.g., FIG. 5 where bore 300is not threaded) and operatively connected to gear teeth or threads 1260of adjusting screw 1200 through opening 320 of body 210. As controlscrew 1500 is turned in the direction of arrow 4032 (see FIG. 5),adjusting screw 1200 will move in the direction of arrow 214. On theother hand, as control screw 1500 is turned in the opposite direction ofarrow 4032 (see FIG. 5), adjusting screw 1200 will move in the oppositedirection of arrow 214. Turning of adjusting screw 1200 causes wedgingmembers 700 and 900 to move: (a) respectively in the directions ofarrows 702 and 900 or (b) respectively in the opposite directions ofarrows 702 and 902, each case depending on the rotative direction ofadjusting screw 1200 or gear.

By controlling the expansion or retraction of wedging members 700 and900, a surgeon can control the amount of distraction caused by wedgingmembers 700 and 900 upon a pair of spinous processes where adjustableimplant 200 is placed in between. Such control can allow a surgeon touse a single adjustable implant 200 to properly distract spinousprocesses 100 and 110 of multiple sizes and configurations (see e.g.,FIGS. 16-18). In prior art devices, such controlled amount ofdistraction is not available and spinous processes 100 and 110 ofdifferent sizes or configurations require multiple sizes of distractionimplants.

With prior art distraction implants the surgeon may not be able to tellthe proper size of the prior art distraction implants required for aparticular set of spinous processes 100 and 110, and will select a firstprior art implant of a first size and attempt to implant same andrealize that the desired amount of distraction is not obtained (becausethe selected prior art implant is too small) or that too muchdistraction is obtained (because the selected prior art implant is toolarge). If the distraction amount is too small the surgeon will have toremove the selected prior art implant and select a different prior artimplant (of larger size) hoping that this second implant will provide anappropriate amount of distraction. This slows down the implantationprocess and unnecessarily aggravates the tissue and bony area aroundspinous processes 100 and 110. If the distraction amount is too large(beyond having to implant a second implant) damage may actually occurfrom excessive distraction.

FIGS. 1-15 show more particularly the construction of adjustable spinedistraction implant 200. A body/housing 210 provides first 220 andsecond 230 end portions. A gear case or body 210 has a dual diametersocket that includes large internally threaded bore 330 and smallernon-threaded bore 300. Bore 300 is receptive of control screw 1200. Bore330 is receptive of threaded locking screw or nut 1600. As shown in FIG.5, the locking screw 1600 on the upper end, and base 310 on the lowerend limits the amount of vertical movement (schematically indicated byarrow 1558 of FIG. 5) of control screw 1500 thus allowing control screw1500 to rotate adjusting screw or gear 1200 and finally expand orretract wedging members 700 and 900.

As shown in FIGS. 8 and 10, control screw 1500 can have a tool (e.g.allen wrench) receptive socket 1540 that is receptive of a tool end 5020and external thread 1530. The tool end portion 5020 of tool 5120interlocks with socket 1540 (e.g. allen wrench receptive) of threadedcontrol screw 1500. As shown in FIGS. 8 and 9, locking screw or nut 1600can have a tool (e.g. star) receptive socket 1650 that connects withtool 5030. The tool end portion 5030 interconnects with socket (e.g.star drive) 1650 of locking screw or nut 1600. Locking screw or nut 1600can have external threads 1640.

Tool 5020 can be used to turn control screw 1500 which in turn rotatesadjusting screw 1200 which in turn expands or retracts wedging members700 and 900. Tool 5030 can be used to frictionally lock control screw inplace and prevent further movement of adjusting screw 1200 or wedgingmembers 700 and 900.

After locking screw or nut 1600 is loosened, second tool or driver 5020can be used to rotate control screw 1500 and thus rotate adjusting screwor gear 1200 in a selected direction (such as that indicated by arrow214 in FIG. 5, or in the opposite direction of arrow 214). As shown inFIGS. 4, 5, and 8, adjusting screw or gear 1200 can be rotativelyconnected to body 210 through first longitudinal bore 270 andlongitudinal bore 580. Second end 1220 of adjusting screw or gear 1200is supported by and rotates in longitudinal bore 580 while head 1230rotates in and is supported by first longitudinal bore 270.

FIGS. 5 and 8 shows one embodiment of adjusting screw 1200 beingoperably connected to wedging members 700 and 900, and how control screw1500 can be operably connected to adjusting screw 1200 thereby makingcontrol screw 1500 operably connected to wedging members 700 and 900.FIG. 6 is a schematic view of adjustable implant 200 where wedgingmembers 700 and 900 are in a retracted state. FIG. 7 is a schematic viewshowing wedging members 700 and 900 in a partially to completelyextended or expanded state.

FIGS. 4, 6, 7, and 18 schematically show that, as adjusting screw 1200rotates in the direction of arrow 214 (or from the opposite view in thedirection of arrow 1556 shown in FIG. 7), wedging members 700 and 900respectively move in the directions of arrows 702 and 902. Similarly, ifrotation is in the opposite direction of arrow 214 (or in the oppositedirection of arrow 1556 in FIG. 7), wedging members 700 and 900 moverespectively in the opposite directions of arrows 702 and 902. As shownin FIGS. 6 through 8, middle section 1300 of adjusting screw or gear1200 can be operatively connected to arm 800 of wedging member 700through threaded or gear toothed area 1310 cooperating with threaded arm800. Middle section 1300 of adjusting screw or gear 1200 can beoperatively connected to arm 1000 of wedging member 900 through threadedor gear toothed area 1320 cooperating with threaded arm 1000. Such athreaded or gear toothed connection can be referred to as a rack andpinion type connection. Additionally, as shown in FIG. 5 control screw1500 can be operatively connected to adjusting screw or gear 1200 bymeans of threaded or gear toothed area 1260 of adjusting screw or gear1200. Such a threaded or gear toothed connection can be referred to as aworm gear type connection.

Wedging members 700 and 900 can be slidably connected to body 210 ofadjustable implant 200 through a series of pins and tracks. As shown inFIGS. 6 through 8 body or gear box 210 can be comprised of first end 250and second end 252. Guide 500 can be connected to body 210 by first andsecond longitudinal arms 440 and 460. First end 250 can have a raisedportion 370 and guide 500 on second end 252 can include a base 550. Asshown in FIG. 8, raised portion 370 can include track 420 and track 430.Also as shown in FIG. 8 base 550 can include track 560 and track 570.Opposed tracks 420, 430, 560, and 570 can form a three dimensional tracksystem for wedging members 700 and 900 to slide back and forth in (asschematically indicated in FIGS. 6, 7, 15, and 18.

Adjustment screw 1200 can be rotatively connected to body 210 throughbore 270 in second end and bore 580 in guide 500. Tip 1220 canrotatively sit in bore 580 and head 1230 can rotatively sit in bore 270.

In one embodiment body 210 can include a cover for head 1230 which wouldprevent adjusting screw 1200 from coming out of body or gear box 210.Although not shown in another embodiment to prevent adjustment screwfrom falling out of body 210 wherein a threaded or gear toothed area1260 can extend a length 1270 from top 1240 of head 1240 to a pointbefore reaching the base 1250, after which point non-threaded area 1230of head 1230 will be found. Control screw 1500 will threadably engagethe threaded portion 1260 of adjustment screw 1100, but control screw1500 will resist longitudinal movement of adjustment screw 1200 bythreads 1530 contacting the non-threaded area 1230 of adjustment screw1200 and not allowing longitudinal movement.

As shown in FIGS. 1, 2, 6-8, 11, 14, and 15, wedging members 700 and 900can be constructed substantially identical. Wedging member 700 can besubstantially identical to wedging member 900 but essentially rotatedone hundred and eighty degrees so that the bottom 720 of wedging member700 is in line with the top 910 of wedging member 900. Each of thewedging members 700, 900 can respectively be provided with a gear panelor arm 800, 1000 having a threaded or toothed rack 802, 1002. Wedgingmember 700 has gear panel or arm 800 with toothed rack 802. Wedgingmember or plate 900 has gear panel or arm 1000 with toothed rack 1002.Therefore, only the construction of wedging member 900 will be describedin detail. Wedging member 900 can comprise top 910, bottom 920, interiorportion 930, exterior portion 940, curved portion 950. Wedging member900 can also include threaded or gear toothed arm 1000 and four rails orprongs 960, 970, 980, and 990.

Looking at FIGS. 6 through 8, and 15 through 18, it can be seen thatwedging member 900 can be slidably connected to body 210 through itsrails or prongs 960 and 970 slidably connecting to slots 570 and 560 ofthe base 550 of guide 500; and through its rails or prongs 990 and 980slidably connecting to slots 430 and 420 of raised area 370. The fourrails or prongs of wedging member 900 can maintain a straight path forwedging member sliding in the slots of raised area 370 of body 210, andbase 550 of guide 500. Similarly the rails or four prongs of wedgingmember 700 can maintain a straight path for wedging member sliding inthe slots of raised area 370 of body 210, and base 550 of guide 500. Theextent of expansion and retraction of wedging members 700 and 900 can becontrolled by threaded area 1310 cooperating with threaded arm 800 ofwedging member 700, and threaded area 1320 cooperating with threaded arm1000 of wedging member 900. In this manner wedging members 700 and 900can be held in place at a selected amount of expansion or contraction(regardless of where they have been expanded or retracted to) as long aswedging members' 700 and 900 prongs remain at least partially sitting inthe specified slots.

Each wedging member 700 or 900 can maintain a straight (generallyvertical) path for wedging member 700, 900 sliding in the slots 420,430, 560, and 570. The extent of expansion and retraction of wedgingmembers/plates 700 and 900 can be controlled by screw/gear 1200. In thismanner plates/wedging members 700 and 900 can be held in place at aselected amount of expansion or contraction (regardless of where theyhave been expanded or retracted to) as long as wedging members' 700 and900 rails 760,770, 780, 790 (for wedging member 700) and rails 960,970,980, and 990 (for wedging member 900) remain at least partially sittingin the specified slots.

To ensure that the prongs remain at least partially in the slots, theradial extent of threading for threaded areas 1310 and 1320 can beselected by having non-threaded areas 1330 and 1340. That is when theradial extent of the threaded area is reached, the specific wedgingmember (700 and/or 900) will stop its expansion. As shown in FIG. 4, asecond safe guard can be provided in the amount of radial threading 1260for the worm gear portion of adjusting screw 1200. In a preferredembodiment, an angular amount 1280 of about 120 degrees of radialthreading 1260 can be provided which will restrict further rotation ofscrew 1200—when the threads angularly reach point 1262 or 1264 (see FIG.5).

As shown in FIG. 8 arms 440 and 460 can include notches 450, 452, 470,and 472 to accommodate the rails or prongs of wedging members 700 and900, and allow complete retraction of wedging members 700 and 900.Without these notches the prongs of wedging members 700 and 900 wouldprevent complete retraction.

FIG. 11 is a perspective view of adjustable implant 200 placed on itsside. In this embodiment wedging members 700 and 900 are completelyretracted and their exterior surfaces 740 and 940 are flush with raisedarea 370 of second end 220 and base 550 of guide 500. Making theexterior surfaces flush when wedging members 700 and 900 are fullyretracted resists damage to bone and tissue during the initial insertionprocess (as no sharp edges are seen).

After the desired or proper expansion or retraction is obtained withwedging members 700 and 900, control screw 1500 can be locked in placeby locking screw 1600. Locking screw 1600 can include first end 1610,second end 1620, and threaded area 1640. Locking screw 1600 can havebore 1650 which allows access to control screw 1500 even when lockingscrew 1600 is connected to the bore 330 for locking screw 1600. Bore1650 allows locking screw to be in place even when adjusting controlscrew 1500. This feature reduces the amount of free parts the surgeonmust keep track of during the operation (and prevents control screw 1500and locking screw 1600 from falling out during an implantationprocedure). In one embodiment a cover for bore 330 can be provided whichprevents locking screw 1600 from being completely removed from body 210.After the desired amount of distraction is obtained, preferably, controlscrew 1500 is locked in place by second end 1620 of locking screw 1600squeezing control screw 1500 against base 210 of bore 300. Thissqueezing frictionally locks in place control screw 1500. Even if notfrictionally locked by locking screw 1600, the status of being a wormgear connection between control screw 1500 and threads 1260 ofadjustment screw 1200, would tend to be self locking. However, withoutlocking screw 1600, vibrations and other movements of implant 200 overtime may tend to cause adjustment screw 1200 to rotate and causeunwanted movement of wedging members 700 and 900. Preferably, whenlocking screw 1600 is locked in place, first end 1610 is flush with top232 of body 210.

Adjustable implant 200 and its components can be made of a number ofmaterials, including but not limited to, stainless steel, titanium,ceramics, plastics, elastics, composite materials or any combination ofthe above. In addition, the modulus of elasticity of the implant can bematched to that of bone, so that the implant is not too rigid. Theflexibility of the implant can further be enhanced by providingadditional apertures or perforations throughout the implant.

Preferably, adjustable implant provides for distraction in the range ofabout 8 mm to about 11 mm in one embodiment (more preferably about 8 mmto about 10.7 mm), and in another embodiment in the rage of about 10 mmto about 15 mm (more preferably about 10.5 mm to about 14 mm).

In one embodiment an implantation guide 500 can be provided. Positionedat the other end of body 210 can be guide 500. Guide 500 can betriangularly-shaped so as to be a pointed and arrow-shaped guide.Alternatively, guide 500 can be in the shape of a cone with lateraltruncated sides along the longitudinal axis wedging members 700 and 900.Guide 500 can include a threaded bore 590. In other embodiments guide500 can be bulbous, cone-shaped, pointed, arrow-shaped, and the like, inorder to assist in the insertion of adjustable implant 200 betweenadjacent spinous processes. Preferably, the insertion technique disturbsas little of the bone and surrounding tissue or ligaments as possible inorder to (a) reduce trauma to the site and facilitate early healing, and(b) not destabilize the normal anatomy. In various embodiments there isno requirement to remove any of the bone of the spinous processes anddepending on the anatomy of the patient, there may be no requirement toremove or sever ligaments and tissues immediately associated with thespinous processes.

In one embodiment guide 500 has a cross-section which is adjacent to thecross section of completely retracted wedging members 700 and 900 and ofsimilar shape. Where guide 500 and completely retracted wedging members700 and 900 have elliptical cross sections, preferably the majordimension of guide's 500 cross section is about equal to the majordimension of completely retracted wedging members 700 and 900 crosssection, and guide's 500 minor dimension about equal to completelyretracted wedging members 700 and 900 cross section. In this embodiment,guide 500 can extend from body 210 of implant 200 with a cross-sectionwhich reduces in size in a direction away from body 210. In anotherembodiment, guide 500 can be cone-shaped with a base located adjacentwedging members 700 and 900. Further, in one embodiment guide 500 canhave a base cross-section about the same as an oval cross-section ofcompletely retracted wedging members 700 and 900.

In one embodiment guide 500 has faces 520 and 530 which are at about 45degree angles (other angles, such as by way of example only, from about30 degrees to about 60 degrees, and from about 25 to about 75 degreesare also envisioned), with a tip 540 so that adjustable implant 200 canbe more easily urged between the spinous processes.

In one embodiment, adjustable implant 200 can have a central bodyportion, the central body portion including wedging members 700 and 900,with a longitudinal axis 212. Extending from the central body portioncan be a first wing 1800 and second wing 2000 which can be substantiallyperpendicular to longitudinal axis 212. Wings 1800 and 2000 can resistthe tendency of adjustable implant to slide out from between spinousprocesses 100 and 110. In one embodiment second wing 2000 can detachablyconnectable to adjustable implant 200. In one embodiment second wing2000 can be laterally adjustable relative to first wing 1800 toaccommodate spinous processes of varying sizes and dimensions—arrows2002 and 2004 in FIG. 17 schematically indicate lateral adjustment ofsecond wing 2000. Making wing 2000 detachably connectable facilitatesinsertion of adjustable implant between spinous processes 100 and 110,such as through guide 500.

In one embodiment, completely retracted wedging members 700 and 900 canhave an elliptical cross section with a major axis which issubstantially perpendicular to a major dimension (e.g., longitudinalaxis) of first wing 1800 along longitudinal axis. Making these two axessubstantially perpendicular facilitates proper positioning of adjustableimplant 200 between selected spinous processes 100 and 110, and ensuringthat substantial portions of wedging members 700 and 900 come in contactwith both the upper and lower spinous processes so that the reactionloads can be more evenly distributed on the spinous processes by wedgingmembers 700 and 900 during implantation and subsequent spinal columnmovements after implantation.

Wings 1800 and 2000 which are not perpendicular to longitudinal axis 212are envisioned, and can be offset by 5, 10, 15, 20, and/or 25 degreesfrom the perpendicular and/or any range without such amounts. As shownin FIG. 3, first wing 1800 can include an upper area 1830 and a lowerarea 1840. Upper area can include a rounded end 1832. Rounded end 1832can be designed to accommodate the anatomical form or contour variousportions of the vertebrae, for example L4 (for a L4-L5 placement) or L5(for a L5-S1 placement) superior lamina of the vertebra. It is to beunderstood that the same shape or variations of this shape can be usedto accommodate other lamina of any vertebra. The lower portion 1842 canalso be rounded in order to accommodate the vertebrae.

In one embodiment guide 500 can include a threaded bore 590 whichaccepts a screw 2130 in order to hold a second wing 2000 in position.With the second wing 2000 in position, the screw 2130 when it ispositioned in the threaded bore 590 can engage and hold second wing 2000in position relative to first wing 1800.

First and second wings 1800 and 2000 can come in a variety of shapes inorder to provide for variations in the anatomical form of the spinousprocesses. Such shapes can be as depicted in FIGS. 103, 104, 105, 106,and 107 of U.S. Pat. No. 7,101,375. In these configurations, the winghas an upper portion and a lower portion. In FIG. 104, the lower portionis thicker than the upper portion in order to accommodate the spinousprocess, where the lower spinous process is thinner than the upperspinous process. In FIG. 105, both the upper and lower portions areenlarged over the upper and lower portions of FIG. 103 to accommodateboth the upper and lower spinous processes being smaller. That is to saythat the space between the upper and lower portions of the first andsecond wings are reduced due to the enlarged upper and lower portions ofthe second wing. Alternative embodiments of second wings 2000, as shownin FIGS. 104 and 105, are depicted in FIGS. 106 and 107. In these FIGS.106 and 107, the second wing accommodates the same anatomical shape andsize of the spinous processes as does the second wing in FIGS. 104 and105 respectively. However, in the embodiments of the second wing ofFIGS. 106 and 107, substantial masses have been removed from the wings.The upper and lower portions are essentially formed or bent in order toextend from the central portion of the second wing.

FIGS. 12 and 13 are views of second wing 2000 and connecting screw 2130.Connecting screw 2130 can comprise threaded area 2140 and reduced crosssectional area 2150. Reduced cross sectional area 2150 can allow secondwing member 2000 to slide (and be longitudinally adjustable) relative toscrew 2130 (and first wing member 1800). Second wing member 2000 caninclude track 2110 and track can include threaded area 2120. Second wingmember 2000 can include first end 2010, second end 2020, and cutout area2050. Cutout area 2050 can be shaped to fit around the outer surface ofguide 500. Alternatively, cutout area 2050 can be enlarged to allow fulldistraction of wedging members 700 and 900 (see e.g., FIG. 35 withsecond wing 2000′″ and cutout area 2050′″).

FIG. 15 is a perspective view of adjustable implant 200 having first andsecond wedging members 700 and 900 extended in the directions of arrows702 and 902 and control screw 1500 being turned in the direction ofarrow 4032, causing adjusting screw or gear 1200 to turn in thedirection of arrow 214 along longitudinal centerline 212.

FIG. 17 is a perspective view of adjustable implant 200 placed inbetween spinous processes 110 and 120. Preferably a longitudinal line2008 through second wing 2000 will be parallel to a longitudinal line1808 going through first wing 1800. Arrows 2002 and 2004 schematicallyindicate the adjustability of second wing 2000 relative to first wing1800 by varying the distance D.

FIG. 18 is a side perspective view of adjustable implant 200 showing atool 4030 being used on the control screw 1500 to adjust adjusting screw1500 and change the state of first 700 and second 900 wedging members.In FIG. 18 is shown both line 212 (which is the axis of rotation ofadjusting screw or gear 1200) and a line 218 which is perpendicular tothe axis of rotation of control screw 1500 (schematically indicated byarrow 4032). As shown in FIG. 1, line 218 can be spaced apart by thedistance A from the axis of rotation of control screw 1500. As can beseen the axis of rotation of control screw 1500 does not intersect theaxis of rotation of adjusting screw or gear 1200.

Adjustable implant 200 can be positioned adjacent to upper and lowervertebrae 120 and 130. Extending upwardly from vertebrae 120 and 130 arethe upper and lower spinous processes 100 and 110. In a preferredembodiment, the fit of adjustable implant 200 between spinous processes100 and 110 can be such that wings 1800 and 2000 do not touch spinousprocesses 100 and 110. One advantage of wings 1800 and 2000 is that theyresist dislodgment of adjustable implant 200 from between spinousprocesses 100 and 110.

Preferably, during the surgical process first and second wedging members700 and 900 of adjustable implant 200 are urged between spinousprocesses 100 and 110. After this has occurred, second wing 2000 can beguided by the other sides of the spinous processes from a path whichcauses the plane of second wing 2000 to move substantially parallel tothe plane of first wing 1800 until screw 2130 can be placed in threadedbore 590 of guide 500. Bolt 2130 can be tightened to secure second wing2000.

In one embodiment a second wing 2000 is not used where it was deemedimpractical or unnecessary to use a second wing 2000.

In one embodiment neither a first 1800 nor a second 2000 wing is usedwhere the anatomy between the spinous processes 100 and 110 was suchthat it would be undesirable to use either a first or second wing.

In one embodiment the spinous processes 100 and 110 can be accessed anddistracted initially using appropriate instrumentation, and adjustableimplant 200 can be inserted and adjusted in order to maintain andachieve the desired distraction. In another embodiment the spinousprocess can be accessed and adjustable implant 200 appropriatelypositioned. Once positioned, implant 200 can be expanded in order todistract the spinous processes or extend the distraction of alreadydistracted spinous processes. Accordingly, adjustable implant 200 can beused to create or increase a previously created distraction, or tomaintain a distraction which has already been created.

FIGS. 19-23 show an instrument or tool 5000 that can be used to rotateeither the control screw 1500 and/or the locking screw/nut 1600 andadjust adjustable implant 200. Tool 5000 can include body 5010, shaft5014, control screw head 5020, locking screw head 5030, driver 5120,driver 5130, counter torque handle 5200, base 5300, and set prongs 5310,5320. Torque handle 5200 can be connected to body 5010 and enables asurgeon to hold and support the tool/instrument 5000. Driver 5130 can beslidingly and rotatively connected to body 5010. Driver 5130 can includelocking screw head 5030. Driver 5120 can be slidingly and rotativelyconnected to driver 5130. Driver 5120 can include control screw head5020. Driver 5130 can be connected to shaft 5134 which itself isconnected to locking screw head 5030. Base 5300 can be connected to body5010 and include two set prongs 5310 and 5320. Set prongs 5310 and 5320can locate or set tool 5000 relative to body 210 of adjustable implant200 by matching set prongs 5310 and 5320 with openings 5310′ and 5320′.Once set the individual drivers 5120 and 5130 can be used to drivecontrol screw head 5020 and locking screw head 5030 which respectivelywill turn control screw 1500 and locking screw 1600. Arrows 5121 and5122 schematically indicate slidable movement of driver 5120. Arrow 5017schematically indicates rotation of driver 5120 (which can also be inthe opposite direction). Arrows 5015 and 5016 schematically indicateslidable movement of driver 5130. Arrow 5017 schematically indicatesrotation of driver 5130 (which can also be in the opposite direction).Tool 5000 is a preferred tool in that it allows both control screw 1500and locking screw 1600 to be manipulated with a single instrument.Additionally, it can optionally have a placement system (body 5300 andprongs 5310 and 5320). Body 5300 can be a distal flange or bracket thatcarries one or more projections or prongs 5310 and 5320. If the optionalbody 5300 is employed, the gear case or body 210 carries sockets 5310′and 5320′ that are sized and shaped correspondingly to projections 5310and 5320. In this fashion, the surgeon can interlock the projections5310 and 5320 with the sockets 5310′ and 5320′ to help rigidify theconnection of the tool or instrument 5000 to the body or gear case 210when an adjustment of either of the screws 1500 or 1600 is required.

FIGS. 24-27 show another embodiment of the apparatus of the presentinvention, designated by the numeral 200A. The embodiment of FIGS. 24-27is basically the same as the embodiment of FIGS. 1-23. However, thefirst and second fixtures or wings 1800′, 2000′ are respectivelyprovided with prongs or projections or spikes 1872, 1882 which enhancegripping of the spine 30 (and spinous processes 100 and 110).

FIGS. 28-30 show another embodiment of the apparatus of the presentinvention, designated generally by the numeral 200B. In FIGS. 28-30, theimplant 200B is similar in construction to the embodiment of FIGS. 1-23with the exception of the shape of the wings 1800″, 2000″ beinggenerally rectangular, but also providing rounded or curved endportions. The first wing 1800″ provides upper and lower rounded orcurved end portions 1830″, 1840″. The second wing or fixture 2000″provides upper and lower rounded or curved end portions 2030″,2040″. Aswith the preferred embodiment, the second fixture or wing 2000″ providesa concavity 2050″ that is receptive of body 210. As with the preferredembodiment, a fastener 2130 enables attachment of second fixture or wing2000″ to body 210 using fastener 2130 with a track/slot 2110″ as withthe embodiment shown in FIG. 13. In one embodiment concavity 2050″ canbe expanded to allow wedging members 700 and 900 to be fully distractedeven where second wing 2000″ is placed over wedging members 700 and 900.

FIGS. 31-32 show yet another embodiment, designated generally by thenumeral 200C. Adjustable implant 200C provides the same basicconstruction of the embodiment of FIGS. 1-18 with the addition of aflexible sleeve 2500 that is placed over the body 210 (and wedgingmembers 700 and 900) as shown in FIGS. 31 and 32. The sleeve 2500 has ahollow bore or open ended cavity 2510 that enables the sleeve 2500 tooccupy a position on body 210, basically covering wedging members 700 an900, when the wedging members/plates 700 and 900 are expanded orretracted, the sleeve acts as an interface or cushion in between thewedging members 700 and 900 and the surrounding tissue. This can preventpinching, tearing, or damage to the surrounding tissue.

FIGS. 33 through 43 show one embodiment for laterally adjusting thesecond wing relative to the first wing with another embodiment of secondwing 2000′″. FIGS. 36-43 show an instrument or tool 6000 that can beused to slidingly adjust/clamp second wing 2000′″ relative to first wing1800′″ of various adjustable implants. Tool 6000 can include body 6010,shaft 6014, wing fastener screw head 6020, sliding adjuster screw head6030, driver 6120, driver 6130, counter torque handle 6200, base 6300,and set prongs 6310, 6320. Torque handle 6200 can be connected to body6010 and enables a surgeon to hold and support the tool/instrument 6000.Driver 6130 can be slidingly and rotatively connected to body 6010.Driver 6130 can include sliding adjuster screw head 6030. Driver 6120can be slidingly and rotatively connected to driver 6130. Driver 6120can include fastener screw head 6020. Base 6300 can be connected to body6010 and include two set prongs 6310 and 6320. Set prongs 6310 and 6320can locate or set tool 6000 relative to second wing 2000′″ of adjustableimplant 200 by matching set prongs 6310 and 6320 with openings 6310′ and6320′. Once set the individual driver 6130 can be used to slidinglyadjust second wing 2000′″ relative to first wing (for a clamping effect)of adjustable implant 200. When the proper adjustment between the twowings is achieved, driver 6120 can be used to lock fastener 2130 withcontrol screw head 6020. By adjusting second wing 2000′″ closer to theother wing (in a clamping motion), the two wings can grab hold of and/orbite into spinous processes 100 and 110 to resist relative movementbetween the adjustable implant and the spinous processes. Arrow 6017schematically indicates rotation of driver 6130. Arrows 6018schematically indicate movement of second wing 2000′″ in a clampingmotion (relative to first wing 1800 which is not shown). Body 6300 canbe a distal flange or bracket that carries one or more projections orprongs 6310 and 6320. If the optional body 6300 is employed, the secondwing 2000′″ carries sockets 6310′ and 6320′ that are sized and shapedcorrespondingly to projections 6310 and 6320. In this fashion, thesurgeon can interlock the projections 6310 and 6320 with the sockets6310′ and 6320′ to help rigidify the connection of the tool orinstrument 6000 to the second wing 2000′″ before adjustment of secondwing relative to the adjustable implant to obtain a clamping motion.After head 6030 is inside of well 2112′″ and attached to gear teeth orthreads 2120′″ second wing 2000′″ will slide along adjustable implantvia opening 2050′″ sliding over adjustable implant. In one embodimentthe amount of adjustment of second wing 2000′″ is limited so that thiswing does not travel over wedge members 700 and/or 900. Projections orprongs 1882 help stabilize adjustable implant relative to the spinalprocesses. In one embodiment opening 2050′″ can be enlarged to allowfull expansion/distraction of wedging members 700 and 900 even wheresecond wing 2000′″ is adjusted over wedging members 700 and 900.

Various alternative embodiments or options for any of the abovedescribed will be described below.

In one embodiment adjustable implant 200 can act as an extension stop.For example, adjustable implant can resist or stop further extensionbetween spinous processes 100 and 110 once the back has been bentbackwardly such that adjustable implant 200 stops further movement ofadjacent spinous processes 100 and 110 towards each other. The distancebetween wedging members 700 and 900 can stop movement spinous processes100 and 110 toward each other. Adjustable implant 200 does not limit theflexion of spinal column 30 (because in flexion spinal column 30 is bentforwardly and spinous processes 100 and 110 move away from each other(and away from wedging members 700 and 900).

In one embodiment only one wedging member 700 is provided. In thisembodiment wedging member 900 can be permanently attached to body 210(and arm 100 either removed entirely or the threading removed). In thisembodiment wedging member can expand or retract based on movement ofadjustment screw 1200. In this embodiment about one half of theadjusting expansion or distraction capability will be available comparedto embodiment where two wedging members 700 and 900 are provided.

In one embodiment only one longitudinal arm 440 is provided. The shapeof wedging members 700 and 900 can be adjusted to compensate for formingan elliptical cross section when completely retracted.

Although not shown, in one embodiment only one adjustable wedging memberor plate 700 (or 900) is provided. In this embodiment it is expectedthat only one half of the adjustability of a two wedge/plate member willbe provided.

Although not shown, in one embodiment a cap can be placed over firstlongitudinal bore 270 which also will prevent adjusting screw 1200 fromleaving first longitudinal bore 270. This cap can also preventadjustable implant 200 from being disassembled after manufacture whichcan prevent improper reassembly. This cap can be laser welded to body210. In one embodiment one or more timing marks can be placed onadjusting screw 1200 (e.g., its head 1230) and body 210 which marks canshow proper alignment of adjusting screw 1200 relative to body 210(ensuring proper installation of the components).

Although not shown, in one embodiment one or more raised areas ordetents can be included on first wing 1800 which can limit the expansionof wedging members 700 and/or 900. These raised areas or detents can actas an additional factor of safety beyond the various amounts ofthreading on adjusting screw 1200 (middle section 1300 and head 1230).

In one embodiment wedging members 700 and 900 have a flat, irregular, orconcave shape.

Surgical Method

With all the ligaments (such as the superspinous ligament) and tissuesassociated with the spinous processes left intact, adjustable implant200 can be implanted essentially floating in position in order to gainthe benefits of extension stop and not limiting flexion. In oneembodiment the spinous processes can be accessed and distractedinitially using appropriate instrumentation, and adjustable implant 200can be inserted and adjusted in order to maintain and achieve thedesired distraction. In another embodiment the spinous process can beaccessed and adjustable implant 200 appropriately positioned. Oncepositioned, implant 200 can be expanded in order to distract the spinousprocesses or extend the distraction of already distracted spinousprocesses. Accordingly, adjustable implant 200 can be used to create orincrease a previously created distraction, or to maintain a distractionwhich has already been created.

Ideally, adjustable implant 200 would be placed close to theinstantaneous axis of rotation of spinal column 30 so that the reactionforces adjustable implant places on spinal column 30 are minimized.

For purposes of surgical implantation of adjustable implant 200 into apatient, the patient is preferably positioned on his side and placed ina flexed (tucked) position in order to distract the upper and lowervertebrae.

In a preferred procedure, a small incision is made on the midline of thespinous processes. The spinous processes are spread apart or distractedwith a spreader. The incision is spread downwardly toward the table, andadjustable implant 200 is preferably inserted upwardly between thespinous processes 100 and 110 in a manner that maintains the distractionof spinous processes. The adjustable implant 200 is urged upwardly untilguide 500 and at least part of wedging member 700 and/or 900 are visibleon the other side of the spinous process. Once this is visible, theincision is spread upwardly away from the table and the retaining unitor second wing 2000 can be attached via screw 2130. Track 2110 can beused to space second wing 2000 relative to first wing 1800 (at least tothe extent of allowable movement through slot 2110). After this hadoccurred, the incisions can be closed.

An alternative surgical approach requires that small incisions be madeon either side of the space located between the spinous processes. Thespinous processes are spread apart or distracted using a spreader placedthrough the upper incision. From the lower incision, adjustable implant200 can be inserted upwardly between spinous processes 100 and 110 in amanner that urges the spinous processes apart. Adjustable implant 200can be urged upwardly until guide 500 and at least part of wedgingmember 700 and/or 900 are visible through the second small incision inthe patient's back. Once this is visible, second wing 2000 can beattached to guide 500 through screw 2130. After this has occurred, theincisions can be closed.

The advantage of the above two surgical procedures is that a surgeon isable to observe the entire operation, where he can look directly downonto the spinous processes as opposed to having to view the procedurefrom positions which are to the right and to the left of the spinousprocesses. Generally, the incision is as small as possible and thesurgeon is working in a bloody and slippery environment. Thus, animplant that can be positioned directly in front of a surgeon is easierto insert and assemble than an implant which requires the surgeon toshift from side to side. Accordingly, a top-down approach, as anapproach along a position to anterior line is preferred so that allaspects of the implantation procedure are fully visible to the surgeonat all times. This aides in the efficient location of (i) the adjustableimplant 200 between the spinous processes, (ii) the retaining secondwing 2000 in adjustable implant 200, and (iii) finally screw 2130 inadjustable implant 200.

In one embodiment the method can include implanting adjustable implant200 between two spinous processes 100 and 110, expanding adjustableimplant 200 a first amount, allowing spine 30 to creep or adjust to thisfirst amount of distraction, and then expanding adjustable implant 200 asecond amount, and then allowing a period of time spine 30 to creep oradjust to this new level of distraction. This process could be repeateduntil the desired amount of overall distraction has been accomplished.This stepped wise (and wait) distraction method can be used withinsertion tools prior to the installation of adjustable implant 200. Thetools can be used to obtain the desired distraction using a series ofspinal distraction and spinal creep periods before firs implantingadjustable implant 200.

One embodiment uses a dilator tool 4010 and a distractor tool 4020. Thepatient can be placed prone or lateral. A skin incision can be made overspinous processes 100 and 110 where the stenosis exists. The muscle willbe moved off of the spinous process to the base bilaterally. If thefacet joint is too large, the top can be removed to facilitate placementof adjustable implant 200 at the base of spinous process 110. Theinter-spinous ligament is left intact. A small dilator 4010 can beplaced through the inter-spinous ligament near the base. A seconddistracter 4020′ is then used to open the space up to accommodate thesmaller adjustable implant 200. Adjustable implant is then adjustedcausing wedging members 700 and 900 to expand a desired amount in thedirection of arrows 702 and 902. Adjustment is obtained by rotation of acontrol screw 1500 which rotates an adjustment screw or worm gear 1200.During this expansion process the surgeon can feel the inter-spinousligament. Once taught, adjustable implant 200 can be allowed to sit andsettle for a period of time (such as for five minutes). After thissettling period of time, control screw 1500 can be tightened a bit morecausing wedging members 700 and 900 to expand a bit more and ensure thatthe inter-spinous ligament remains taught. If adjustable implant 200cannot be expanded to a point where there is the desired amount ofstretching of the inter-spinous ligament, then a larger sized adjustableimplant 200′ can be used and adjusted accordingly. Adjustable implantallows the attachment of a second wing 2000 to prevent lateraldislodgment of adjustable implant from spinous processes 100 and 110.Preferably, the area is irrigated with antibiotics and saline and themuscle is injected with local anesthetic and the wound is closed.

FIGS. 16 through 18 show various steps in one embodiment of the methodof implanting adjustable implant 200. FIG. 16 is a perspective view of aportion of a spinal column 30 where adjustable implant 200 is beinginserted between a first spinous process 100 and a second spinousprocess 110 (guide 500 facilitates such insertion). FIG. 17 showsadjustable implant 200 being more fully inserted between a first spinousprocess 100 and a second spinous process 110 and second wing 2000 beingattached. FIG. 18 shows adjustable implant 200 after first 700 andsecond 900 wedging members have been extended more fully (in thedirections of arrows 702 and 902) pushing apart first spinous process100 and second spinous process 110.

INDUSTRIAL APPLICABILITY

From the above, it is evident that the embodiments can be used torelieve pain caused by spinal stenosis in the form of such as thatcaused by central canal stenosis or foraminal (lateral) stenosis.Various embodiments have the ability to flatten the natural curvature ofthe spine and open the neural foramen and the spacing between adjacentvertebra to relieve problems associated with the above-mentioned lateraland central stenosis. Additionally, various embodiments can be used torelieve pain associated with facet arthropathy. Various embodiment canbe implanted with surgery that is minimally invasive and can be used onan outpatient basis.

The following is a list of reference numerals:

LIST FOR REFERENCE NUMERALS (Part No.) (Description) Reference NumeralDescription 10 patient 20 back 30 spinal column 40 vertebrae 50 vertebra60 nerves 70 blood vessels 100 first spinous process 110 second spinousprocess 120 upper vertebra 122 arrow 130 lower vertebra 132 arrow 200implant 202 arrow 210 body 212 longitudinal axis 214 arrow 215 arrow 216plane 218 line 220 first end 230 second end 232 top 240 housing 250first end of housing 252 second end of housing 260 width of first end270 first longitudinal bore 280 base 290 second longitudinal bore 300control screw bore 310 base of control screw bore 320 opening betweencontrol screw bore and first longitudinal bore 330 locking screw bore340 threaded area 350 base of locking screw bore 360 second end ofhousing 370 raised portion 380 first side of raised portion 390 shape400 second side of raised portion 410 shape 420 first track 430 secondtrack 440 first longitudinal arm 450 notch 452 notch 460 secondlongitudinal arm 470 notch 472 notch 500 insertion guide 510 arrow head520 first face 530 second face 540 tip 550 base 560 first track 570second track 580 longitudinal bore 590 threaded bore for second wing 600distracting unit 610 central body 620 spacer 630 cross section 640ellipse 650 major axis 660 minor axis 670 longitudinal axis 700 firstwedging member 702 arrow 710 top 720 bottom 730 interior portion 740exterior portion 742 outermost point of exterior 750 curved portion 760first prong 770 second prong 780 third prong 790 fourth prong 800threaded arm 802 geared or toothed area 810 tip of threaded arm 820shape of tip 830 length of threaded arm 900 second wedging member 902arrow 910 top 920 bottom 930 interior portion 940 exterior portion 942outermost point of exterior 950 curved portion 960 first prong 970second prong 980 third prong 990 fourth prong 1000 threaded arm 1002geared or toothed area 1010 tip of threaded arm 1020 shape of tip 1030length of threaded arm 1200 adjusting screw or worm gear 1210 first end1220 second end 1230 head 1240 top of head 1250 base of head 1260threaded area 1262 end of threaded area 1264 end of threaded area 1270length of threads from top to base of head 1280 angular extent ofthreaded area 1300 middle section 1310 first threaded area 1320 secondthreaded area 1330 first non-threaded area 1340 second non-threaded area1360 tip 1500 control screw 1510 first end 1520 second end 1530 threadedarea 1540 receiving area for adjusting tool 1550 arrow 1554 arrow 1556arrow 1558 arrow 1600 locking screw 1610 first end 1620 second end 1630reduced area of second end or tip 1640 threaded area 1650 receiving areafor adjusting tool 1800 first wing 1830 upper area 1832 rounded area1840 lower area 1842 rounded area 1872 plurality of spikes orprojections 1882 plurality of spikes or projections 2000 second wing2002 arrow 2004 arrow 2010 first end 2020 second end 2030 upper area2040 lower area 2050 cutout area 2060 first side 2070 second side 2080middle section 2090 base of middle section 2100 curved area of base 2110track 2120 threaded area 2130 connecting screw 2140 threaded area 2150reduced cross sectional area 2160 receiving area for adjusting tool 2500flexible sleeve member 2510 opening or bore 3000 first distractionamount 3010 second distraction amount 3020 extension stop 4000instrumentation 4010 dilator tool 4020 distractor tool. 4030 adjustingtool 4032 arrow 4040 adjusting tool 4042 arrow 5000 tool 5010 body 5014shaft 5015 arrow 5016 arrow 5017 arrow 5020 control screw head 5030locking screw head 5120 driver 5121 arrow 5122 arrow 5123 arrow 5130driver 5134 body 5200 counter torque handle 5300 base 5310 set prong5320 set prong 6000 tool 6010 body 6014 shaft 6015 arrow 6016 arrow 6017arrow 6018 arrows 6020 locking screw head 6030 adjustable rack screwhead 6120 driver 6121 arrow 6122 arrow 6123 arrow 6130 driver 6200counter torque handle 6300 base 6310 set prong 6320 set prong

All measurements disclosed herein are at standard temperature andpressure, at sea level on Earth, unless indicated otherwise. Allmaterials used or intended to be used in a human being arebiocompatible, unless indicated otherwise.

It will be understood that each of the elements described above, or twoor more together may also find a useful application in other types ofmethods differing from the type described above. Without furtheranalysis, the foregoing will so fully reveal the gist of the presentinvention that others can, by applying current knowledge, readily adaptit for various applications without omitting features that, from thestandpoint of prior art, fairly constitute essential characteristics ofthe generic or specific aspects of this invention set forth in theappended claims. The foregoing embodiments are presented by way ofexample only; the scope of the present invention is to be limited onlyby the following claims.

1. An adjustable implant comprising: a central body configured to beinserted between adjacent first and second spinous processes, thecentral body having a longitudinal axis; and a first wedging member, thefirst wedging member configured to expand and retract relative to thecentral body in a first linear direction perpendicular to thelongitudinal axis to engage the first spinous process; a first wingextending from the central body substantially perpendicular to thelongitudinal axis; wherein the first wedging member is substantiallyflush with an exterior surface of the central body when the firstwedging member is in a retracted position; wherein a worm gear isoperably connected to the first wedging member and adjusts the firstwedging member; wherein the worm gear has a threaded portion which isoperably connected to the first wedging member and a non-threadedportion which limits the amount of expansion to the first wedgingmember.
 2. The adjustable implant of claim 1, wherein the implantincludes a second wedging member, the second wedging member beingadjustable relative to the central body, the second wedging member beingfurther adjustable relative to and simultaneously with the first wedgingmember.
 3. The adjustable implant of claim 1, wherein an adjusting screwis operably connected to the worm gear.
 4. The adjustable implant ofclaim 3, wherein a locking screw is used to lock in place the adjustingscrew.
 5. The adjustable implant of claim 3, wherein the worm gear has alongitudinal axis and the adjusting screw limits the amount oflongitudinal movement of the worm gear.
 6. The adjustable implant ofclaim 1, wherein, after the implant has been positioned between spinousprocesses, a tool operably connected to the first wedging member canmake at least one complete revolution without being disconnected fromthe first wedging member.
 7. The adjustable implant of claim 1, whereina tool operably connected to the first wedging member rotates about aline which is parallel to the intersecting plane.
 8. The adjustableimplant of claim 1, wherein expansion and retraction of the firstwedging member occurs in a line which is perpendicular to a planeintersecting the implant, and a tool operably connected to the firstwedging member rotates about a line which is not contained in thisintersecting plane.
 9. The adjustable implant of claim 1, whereinexpansion and retraction of the first wedging member occur in a line,and a tool operably connected to the first wedging member does not alsorotate about this line.
 10. The adjustable implant of claim 1, whereinexpansion and retraction of the first wedging member and second wedgingmember occur in a line, and a tool operably connected to the firstwedging member does also not rotate about this line.
 11. The implant ofclaim 1, wherein when in a retracted state, the central body has anelliptical cross section, an oval cross section, rectangular crosssection, or a double trapezoid cross section.
 12. The implant of claim1, wherein the central body has a blunt end and a pointed end and atleast one flat side located between the blunt end and the pointed end,the flat side being adapted to be positioned adjacent to a spinousprocess and to conform to a relatively flat portion of a spinousprocess.
 13. The implant of claim 1, further including a tool that canguide the placement of the central body between spinous processes. 14.The implant of claim 1, wherein the implant includes a second wing beingdetachably connectable to the implant.
 15. An adjustable implantcomprising: a central body configured to be inserted between adjacentfirst and second spinous processes, the central body having alongitudinal axis; and a first wedging member, the first wedging memberconfigured to expand and retract relative to the central body in a firstlinear direction perpendicular to the longitudinal axis to engage thefirst spinous process; a first wing extending from the central bodysubstantially perpendicular to the longitudinal axis; wherein the firstwedging member is substantially flush with an exterior surface of thecentral body when the first wedging member is in a retracted positionwherein the implant includes a second wedging member, the second wedgingmember being adjustable relative to the first wedging member and thecentral body wherein a worm gear is operably connected to both the firstwedging member and the second wedging member, and the worm gear adjuststhese wedging members wherein the worm gear has first and secondthreaded portions which are respectively operably connected to the firstwedging member and the second wedging member, and first and secondnon-threaded portions which respectively limit the amount of expansionof the first wedging member and the second wedging member.
 16. Theadjustable implant of claim 15, wherein after the implant has beenpositioned between spinous processes, a tool operably connected to thefirst wedging member and second wedging member can make at least onecomplete revolution without being disconnected from these wedgingmembers.
 17. The adjustable implant of claim 15, wherein expansion andretraction of the first wedging member and second wedging member occurin a line which is perpendicular to a plane intersecting the implant,and a tool operably connected to the first wedging member and the secondwedging member rotates about a line which is parallel to theintersecting plane.
 18. The adjustable implant of claim 15, whereinexpansion and retraction of the first wedging member and second wedgingmember occur in a line which is perpendicular to a plane intersectingthe implant, and a tool operably connected to the first wedging memberand the second wedging member rotates about a line which is notcontained in this intersecting plane.
 19. An implant positionablebetween a first spinous process and a second spinous process of thespinal column, the implant comprising: a central body configured to beinserted between the first spinous process and the second spinousprocess, the central body comprising: an adjustment mechanism housinghaving at least a portion of an adjustment mechanism provided therein,and an elongated member extending from the adjustment mechanism housing,the elongated member having a longitudinal axis; first and secondwedging members disposed at least partially within the elongated memberand controllable by the adjustment mechanism, the first and secondwedging members able to linearly expand and retract relative to theelongated member in a direction perpendicular to the longitudinal axisin order to increase or decrease the amount of distraction between thefirst and second spinous processes; a first wing extending from thecentral body substantially perpendicular to the longitudinal axis. 20.An adjustable spinal implant comprising: an implant body positionablebetween spinous processes of the spinal column, the implant body havinga longitudinal axis and having an exterior surface; a first wedgingmember expandable from the implant body in a first linear directionperpendicular to the longitudinal axis and a second wedging memberexpandable from the implant body in a second linear directionperpendicular to the longitudinal axis, wherein the first lineardirection is opposite the second linear direction; gearing that movesthe first and second wedging members between a retracted position and anexpanded position; wherein an upper surface of the first wedging memberand a lower surface of the second wedging member are configured toengage the spinous processes, and wherein the upper and lower surfacesare configured to be flush with the exterior surface of the implant bodywhen in a retracted position; wherein the gearing includes a worm gearis operably connected to at least one of the first and second wedgingmembers; wherein the worm gear has a threaded portion which is operablyconnected to at least one of the first and second wedging members and anon-threaded portion which limits the amount of expansion to the atleast one of the first and second wedging members.
 21. The adjustableimplant of claim 20, wherein the gearing includes an adjusting screwthat engages the worm gear, and a locking screw that enables theadjusting screw to be locked in place.
 22. An adjustable spinal implantcomprising: an implant body positionable between spinous processes ofthe spinal column, the implant body having a longitudinal axis andhaving an exterior surface; a first wedging member expandable from theimplant body in a first linear direction perpendicular to thelongitudinal axis and a second wedging member expandable from theimplant body in a second linear direction perpendicular to thelongitudinal axis, wherein the first linear direction is opposite thesecond linear direction; gearing that moves the first and second wedgingmembers between a retracted position and an expanded position; whereinan upper surface of the first wedging member and a lower surface of thesecond wedging member are configured to engage the spinous processes,and wherein the upper and lower surfaces are configured to be flush withthe exterior surface of the implant body when in a retracted position;wherein a worm gear is operably connected to both the first and secondwedging wedging members; and wherein the worm gear has first and secondthreaded portions which are respectively operably connected to the firstwedging member and the second wedging member, and first and secondnon-threaded portions which respectively limit the amount of expansionof the first wedging member and the second wedging member.
 23. Theadjustable implant of claim 22, wherein the worm gear has a longitudinalaxis and the adjusting screw limits the amount of longitudinal movementof the worm gear.